Introduction

So, you have purchased your miners, you have a building, you have a profitable model, now all you have to do it plug the miners in, right? Not exactly. This is the step in creating a crypto farm that most people see as an afterthought, but this is the farthest thing from the truth.  Power setup and configuration can be a confusing and complex thing, especially when it comes to a crypto mining operation.  In this guide, I will explain in detail every step and component that is required to set up and configure your power for a successful crypto farm.  What qualifies me to write this guide?  Let me introduce myself, my name is Evan El Koury, and I am the owner of Raptor Power Systems, a manufacturer of power distribution units (PDUs), power supplies (PSUs), and transformers for crypto farms, data centers, the military and more.  My company has helped launch gigawatts of crypto farms and has gained experience from interacting and setting up some of the largest crypto mines in the world.  Every day we get inquiries from clients who do not understand the gravity of what they are about to undertake from a power standpoint.  My hope is that this guide, whether you use our company's products or not, will serve as a valuable resource in the setup and configuration of your crypto mining operation.

What is a crypto farm?

This question may seem basic, but I want to make sure that we are covering every single step in the process to ensure that by the time you are done with this guide, you will have a complete understanding from top to bottom of your power system. 

A crypto farm is essentially a data center. While data centers typically house servers for web resources and storage, crypto farms house miners.  Miners can either be graphics processing units (GPUs) or application-specific integrated chips (ASICs).  It is important to understand the difference as the power requirements for each type of miner varies greatly.  If the coin you are mining has a high difficulty, you will most likely be using an ASIC miner, as long as the coin’s algorithm supports it.  GPU miners are typically used for lower difficulty coins.  The current industry trend is moving away from GPU miners, as they are usually not profitable enough to be deployed in mass and cannot be used to mine flagship coins, like Bitcoin (BTC). 

A crypto mine is a collection of miners that are deployed to mine together in a single location that share power and network resources.  Depending on the setup of the crypto farm, they are usually deployed in 1 megawatt lots (1,000,000 watts), though many are much larger or smaller.  I have assisted in deploying crypto mines that were 200 megawatts. So, the size will vary depending on building type and the financial resources behind the operation.

How are Miners Powered?

Most miners do not come with a power supply unit (PSU).  A PSU has to be purchased separately and usually the manufacturer recommends a third party supplier or they will have their own models for sale. Choosing the right PSU for your miner is critical to the efficiency and longevity of your miners.  When selecting a PSU, always take into consideration the following factors: wattage, efficiency, input type, and voltage range.

When choosing the "size" of your PSU in watts, always leave at least a 20% margin for safety and thermal deration.  For example, if your miner runs at 1000 watts, you should select a PSU that is at least 1200 watts.  Beyond deration, in general, board level electronic components that make up the PSU’s motherboard/control boards will run longer and with more stability at 80% of their total power rating.  This will ensure that you get the longest life out of your PSU. 

Efficiency is a crucial factor in selecting your PSU.  It is the amount of power that makes it from the input to the output of the PSU.  For example, a 1000W power supply that is 90% efficient, will supply 900W of power, not 1000W.  To achieve 1000W of continuous power with a 90% efficient PSU you would need a power supply that was rated for 1111W.  Sometimes PSU manufacturers underrate their PSUs to give you a true power rating, but it is important to review the specification sheets of the PSUs you are considering buying to check the true rating of the PSU.  What happens to the power that does not make it from the input to the output?  It is lost as heat.  This causes two major problems for crypto miners.  Firstly, heat is the biggest enemy of crypto farms.  Cooling a facility is not cheap and can require the addition of expensive HVAC systems and fans to keep the temperature from causing miners or PSUs to not run efficiently.  When a PSU heats up past its temperature rating, the efficiency goes down.  Secondly, the amount of power required to power a miner increases as the temperature rises.  For example, if your facility has an average ambient temperature of 75F and you are running a 1111W PSU, the PSU would require 1111W at 90% efficiency to run a 1000W miner.  If the ambient temperature was to rise to 125F your efficiency would drop to 70% (depending on the PSU manufacturer), which means you would require 1300W of input power to achieve 1000W of output power. At this temperature rise, you are wasting power in the form of heat, which means you are paying for power that is not being used for mining.

PSUs have many different types of inputs for power entry, though the most popular is an IEC C-14 or IEC C-20.  Higher wattage PSUs usually have either one C-20 input or two C-14 inputs. Whereas lower wattage PSUs have a single IEC C-14 input.  In the USA, an IEC C-14 is rated for 15 amps and an IEC C-20 is rated for 20 amps.  Europe has lower ratings for the same outlet.  In Europe, an IEC C-13 is rated for 10 amps and an IEC C-20 is rated for 20 amps.  One thing to look out for is the power cord used to power the PSU.  Due to the fact that many types of electronic equipment use an IEC C-14 or IEC C-20 that are rated for much lower than a miner PSU, manufacturers make power cords that have the right connector types on them, but the wire itself is not rated to handle the current needed for a PSU.  Look for a power cord that is rated for at least 20% more than you will be using it for.  Power cord manufacturers always list this specification about their cords due to a wide disparity in current ratings required for different electronic equipment.

The voltage range can be tricky. Standard server PSUs in the USA are usually rated for universal voltage, which means 90VAC to 264VAC.  Miner PSUs, on the other hand, are usually rated for 200VAC to 250VAC.  Make sure that you know what voltage configuration is available at your facility and that it matches the rating from the PSU manufacturer.  Always choose the highest voltage you can that your miner and facility will accommodate. 

Volts, Amps, Watts and How they Relate

Understanding the difference between volts, amps and watts and how they relate is vital to creating a calibrated power system for your crypto farm.  A good way to understand the difference between these is to envision electricity as water moving through a pipe.  Amps are the amount of water that flows through the pipe.  The pressure of that water would be the voltage.  The amount of power that the water provides is the watts.  A good analogy is a water power mill. The amount of power it can generate is based on the amount of water and the rate at which that water is moving.  To calculate watts, take volts x amps.  It is important to know how to make this conversion because PSUs are always rated in watts, but circuit breakers are always rated in amps.  When it comes time to set up your circuit breaker panels you will have to do these calculations to ensure proper rating and safety.

Voltage Configurations

There are three main types of voltage configurations that are available: 3 phase, dual phase, and single phase.  A miner will always run on single or dual phase.  Facilities are always fed with 3 phase power.  What are the differences between these and how do you get from 3 phase to dual phase or single phase?  First, we must define what a phase is and how they interact with each other.

A phase in electricity is the relative displacement between electrical waves of the same frequency. This relative displacement of oscillating current(s) is in respect to each other.

(Above shows a single-phase AC voltage wave in green with a neutral in blue.)

Like the waves found in water, electrical waves of different wavelengths travel at different strengths, which is where the terms single phase, dual phase, and three-phase power come from. Each of these systems of power is measured by their voltage, which is equivalent to water pressure. This can be understood as the electrical current’s desire to relocate from one location to another via pressure. The other form of measurement is current, which is measured in amps and is the rate of flow, or how fast the amount of pressure is behind the electricity's desire to relocate, as well as its ability to move from one location to another.

The speed and manner of flow in the electrical current are both important and rely on each other. In a single or dual phase system, the electrical phases do not and cannot cancel each other out to create a zero-balanced load. Due to the manner in which they oscillate around each other, there is just no way for them to be able to generate a canceling effect to form a balanced load of energy. In a three-phase power system, however, the three oscillating phases are able to cancel each other out to create a zero-balanced load with the two live wires canceling out the third. This third wire can act as a neutral by carrying back the excess current.

Single phase power is the distribution of an alternating power current where all the voltages of the power system vary in unison. This phase of power is mostly found in the home and it supplies electricity for our heating, lighting, and household appliances. The advantages of single-phase electricity are that it is not a complex configuration, the mechanical design is simple, and this type of electrical distribution is abundant and always available. As we saw in the previous image of the single-phase AC voltage wave, the disadvantage of using a single phase power system is that, because there is only one wave current in oscillation around a neutral line, the wave current does not and cannot cancel out even when the electrical input load is balanced. 

(Above shows a single phase AC voltage wave in green with a neutral in blue.)

Dual phase, or split phase, power is the least common power system of the three. However, it can still be found in some control systems. It is least commonly used because, although two wires are used with a neutral, they alternate together like two bike pedals around the neutral wire. The power behind them may be slightly greater than that of a single phase, but the manner of propulsion has not changed and, like the single phase power system, the two phases still provide an inconsistent push forward.  

(Above is a visual of dual phase waveforms with phase 1 in green, phase 2 in blue, and neutral is red.)

Three-phase power is the most powerful conductor of electricity of the three. It is used to distribute large amounts of electricity and is found in industrial businesses and electrical power grids. These grids are used to transfer large amounts of power into homes and businesses worldwide. This transfer from electrical power grids into homes and businesses is where the three-phases of this system is “broken down” into three single-phase systems. This makes such a massive power source usable in smaller, more manageable quantities and, therefore, more applicable in the homes in which they power. The neutral wire in a three-phase power system is used to provide a return path for the excess current. 

(Above shows three phase voltage waveforms. Green is phase 1, red is phase 2 and blue is phase 3.)

The advantages of using three-phase is that the amount of conductor material required is less and the voltage is able to remain stable and regulated. This is because, if you picture the different types of phases in terms of an oar propelling a boat through the water, a single oar provides an inconsistent push forward. This also holds true for the dual, or split phase power system where the two oars act together at the same time. The power behind them may be slightly greater than just the one oar, but the manner of propulsion has not changed and, like the single phase power system, the oars still provide an inconsistent push forward. 

The three-phase system, on the other hand, can be visualized as three oars in equal one-third proportion from each other in a ‘Y’ configuration. Each oar, or phase of electrical current, in the water is providing a push forward while the other two are above the water. Just as one oar, or phase of current emerges from the water, the next oar, or phase of current, enters. This is likened to what you would see on one of those big Casino riverboats that are continuously propelled with the rotating paddles located at the rear of the boat. The continuous propulsion by the many oars provide a smoother and more stable and regulated stream of electrical current of energy from one location to another. Whereas, the canoe that is being propelled forward by one or two oars provide an inconsistent push forward and has a much slower movement from one location to another. 

That said, it is still easy to create an imbalanced load if you are not plugging things in carefully. This is because the three-phase power system is essentially made up of three single phases that are shifted 120 degrees from each other. These three “single-phases” are separated along the banks of outlets and the imbalance comes when one of the phases has a load that is imbalanced in relation to the other banks of outlets.

(Above is a picture of an unbalanced system. Phase or line 3 has a higher load than the other two phases.)

Also, the loads that are plugged in have to be similar. You cannot plug in a 200 watt light bulb and a 200 watt motor into the different banks of plugins because the characteristics of their electrical current are not the same.

We recommend three-phase power systems for its efficiency because what you are essentially trying to do is harness and pull in the power source of a three-phase system and break it down into manageable single & dual phases in order to power your equipment. The efficient power source of the three-phase system cannot be created from a single or dual-phase system. These two, more manageable power sources, must be broken off from a three-phase system.

Additionally, 3 phase power comes in two different forms, delta and wye.  Delta power is three hot lines and ground.  Wye power is 3 hot lines, a neutral, and a ground.  We recommend using wye power whenever possible.  Beyond being easier to balance your load with a wye configuration, circuit breakers at the branch level are much cheaper as they only are required to breaker 1 hot line, vs 2 hot lines in a delta configuration.

What power is typically available from my utility and what voltage should I use?

This is a question I get every day. What voltage will my power company give me and what is the best one to use?  This is a pretty complex question.  To answer this, we must first understand what voltage is being brought in from the utilities’ sub-station. Power companies generate power at a main plant, whether it be coal, solar, wind or hydroelectric.  This power is distributed via high voltage power lines over long distances to sub-stations.  Sub-stations are a collection of transformers and switchgear that route the power to residential and commercial buildings.  A large facility may even have its own sub-station.  The voltage at a sub-station will usually be between 12,000V and 36,000V.  When power gets to a building, there is a transformer that drops the medium voltage down to a useable low voltage.  These voltages are typically 277V/480V 3 phase and 120V/208V 3 phase.  This presents a problem for crypto farms.  Crypto farms need to run at the highest voltage that the miner’s PSU will accommodate, with the maximum voltage being 250V single or dual phase.  277V/480V is usually too high for standard PSUs, though some manufacturers are now offering 277V PSUs, a majority do not.  120V/208V would work if it was in a delta configuration, but two issues arise from that; branch circuit breakers are more expensive in a dual phase 208 power configuration and there is a margin of 42V that is not being used, which lowers your efficiency.  A 120/208V wye power configuration would not work for most PSUs on the market as that would provide a 120V single phase break out which is lower than the current accepted voltage range.  Even if the PSU could run on 120V, it requires a higher current to achieve the same wattage, which is problematic when it comes to price and size of circuit breakers in your power system.

When you have a choice, ALWAYS choose a 415V/240V 3 phase wye power configuration.  This power configuration provides the highest efficiency and has the lowest circuit breakers costs in your main panel and the branch breakers in your PDUs.  A 415/240V 3 phase wye configuration will have 240V single phase line at the outlet of your PDU.

Major Components of a Crypto Mine

When setting up a crypto mine it is important to understand all of the critical components that are used and their relationship to each other.  A complete power system starts with a mains transformer.  This transformer is used to step the utility voltage from 12,000V-36,000V down to either 480V, 415V or 208V.  After the main transformer, there is a main disconnect.  This is a large switch that is used to cut all power off for maintenance or in an emergency.  Not only is it a good idea to have a main disconnect, but it is also usually required to meet electrical codes in the USA and Canada.  After the main disconnect, the power is fed into a main circuit breaker panel.  This is where the power is broken off into different branches that are distributed out to PDU’s (power distribution units) and protection is provided by integrated circuit breakers.  After the circuit breaker panel, the power is routed to PDUs.  PDUs are used to provide multiple outlets that the miner’s PSUs are plugged into.  In summary, the major components of a crypto mine power system are the mains transformer, the main disconnect, a circuit breaker panel, a PDU, and a PSU.

Mains Transformer

Let’s dive into detail about mains transformers and how to make sure you are selecting the right one.  A transformer has 5 major specifications you need to consider. 

1) Primary voltage – this is the input voltage of a transformer.  This is the voltage that is provided by the utility. 

2) Secondary voltage – this is the output voltage of the transformer.  This is the voltage that will power your crypto mine. 

3) Power rating – this is the total power that the transformer to provide.  Power rating is expressed in kVA, kilo volt-amps.  kVA is calculated with the following formula; Single phase amps to VA calculation formula The apparent power “S” in volt-amps is equal to current “I” in amps, times the voltage “V” in volts: S(VA) = I(A) × V(V).  3 phase amps to VA calculation formula.  The apparent power “S” in kilovolt-amps is equal to square root if 3 current “I” in amps, times the line to line voltage “VL-L” in volts: S(VA) = √3 × I(A) × VL-L(V)  = 3 × I(A) × VL-N(V).  

4) Transformer type – there are two types of transformers that are typically used in a crypto mine, isolation transformer, and autotransformer.  In an isolation transformer, the windings can be constructed as a step-up or step-down transformer to match the load in the power system for your crypto mine.  Some advantages of using an isolation transformer are that it prevents the attached electronics from getting harmonics and spikes from the main input power.  There is no connection between the power lines and earth ground. With an isolation transformer, there is no danger in touching the live lines while the body is earth grounded. By connecting the electrical system ground to the neutral conductor on the transformer secondary (output), it eliminates neutral-to-ground voltage and noise. This creates the cleanest possible power for your PSUs.  An autotransformer is lighter in weight and smaller in size as it has fewer windings and a smaller core.  In addition to being lighter and smaller, an autotransformer is less expensive than an isolation transformer.  The advantages listed above are for autotransformers with a voltage ratio up to 3:1, meaning the voltage drop is less than that ratio. Beyond this range, an isolation transformer is more economical.  There is no isolation between the primary winding and the secondary winding. This means that the protection of the equipment is dependent on the electronics that are attached to the transformer.  Standard PSUs have enough protection built in to be powered by an autotransformer. The primary and secondary side of an autotransformer share a common end, if the neutral side of the primary voltage is not grounded, the secondary side will not be either.  The disadvantage of this is if a failure of the transformer occurs it will result in the full input voltage being pushed to the output.  This failure mode would damage any attached PSUs.  The good news is that there are very few cases where an autotransformer has a failure of this magnitude.

5) Enclosure type – there are two types of enclosures that are used for transformers in a crypto mine, NEMA 1 and NEMA 4R.  NEMA is the standard used for electrical connectors and enclosures in the USA and Canada.  The NEMA rating of an enclosure refers to its ability to repel water, dust, and temperature variations.  A NEMA 1 enclosure is used for indoor applications, so if your transformer is going to be located inside of your building then choose a NEMA 1.  A NEMA 4R enclosure is waterproof and is used in outdoor applications.  If your transformer is going to be located outside of your building, use a NEMA 4R enclosure.  NEMA 4R enclosures cost significantly more than a NEMA 1 enclosure, so if you have a choice, always put your transformer inside of your building.

When given a choice, choose an isolation transformer if you are dropping high voltage, 12,000V-36,000V down to 415V, 240V or 208V.  Use an autotransformer when you are dropping 480V down to 415V, 240V or 208V.

Circuit Breaker Panels

A circuit breaker panel is often an overlooked component of a power system.  This is the heart of your power system and careful consideration needs to be taken while selecting what type of panel to use and what type of circuit breakers to install in it.  There are five major areas to consider when selecting a circuit breaker panel.

1) Enclosure type – just like a transformer, there are two major choices to the enclosure type, a NEMA 1 and a NEMA 4R.  These enclosures can come in wall mount or free-standing models.  Typically, freestanding models are used for 1000kVA rating and higher and wall mount enclosures are used for 1000kVa or less.

2) Wiring vs bus bar – there are two ways to make the internal interconnections inside of a circuit breaker panel, with wire or with a copper bus bar.  Wiring is usually used in lower power rated circuit breaker panels.  Wiring a panel is costly but makes the panel easier to customize.  Compliance-wise a wired panel is easier to get UL listed.  Wired panels can be listed to UL 508A, which can be done by the manufacturer without having to actually send the panel out to be tested.  This helps equalize the price increase usually associated with wired panels.  Bus bar panels use a thick copper bus bar to route power internal to the panel.  Bus bars have to be machined, which makes it more costly for small quantities, especially if the panel is customized.  Bus bar circuit breaker panels are UL listed to UL 891.  This certification cannot be done by the manufacturer.  To achieve a UL 891 listing, the manufacturer has to have an NRTL (nationally recognized testing laboratory) test the panel and certify it.  This can be a large cost driver, especially if the panel is customized.  When given a choice, choose a wired panel if it is 1000kVA or less and if the panel needs to be custom (not standard from the manufacturer).  Choose a bus bar panel if the power is larger than 1000kVA.  If the panel is custom and over 1000kVA, weigh the cost differential between having multiple wired panels and a single bus bar panel.

3) Circuit breaker type – there are two types of circuit breakers that can be used in a circuit breaker panel, a thermal circuit breaker or a hydraulic/magnetic circuit breaker.  A thermal circuit trips based on the heat on a power line.  Heat has a direct correlation to the current that is flowing through a wire.  When the temperature reaches a certain point, the circuit breaker trips.  The advantage to a thermal circuit breaker is the cost, they tend to be more economical.  The disadvantage is that they are sensitive to ambient temperature and have to be derated properly to ensure you are getting adequate protection.  The higher the ambient temperature, the current that is required to trip the circuit breaker is lower.  A magnetic/hydraulic circuit breaker is more expensive than a thermal circuit breaker but is not as sensitive to ambient temperature.  If you will have a high ambient temperature, choose a magnetic/hydraulic circuit breaker.  If your environment is temperature-controlled choose a thermal circuit breaker to provide more value.

4) Circuit breaker sizing – choosing the right size for a circuit breaker can be a complicated task.  First, you must understand the type of circuit breaker you are using.  As described above, choose a circuit breaker based on your ambient temperature.  If you are using a hydraulic/magnetic circuit breaker you must derate a straight 20%.  For example, if you are running 100 amps of load, the circuit breaker should be rated for 120 amps, unless you are using a 100% rated circuit breaker, which is uncommon.  If you are using a thermal breaker, refer to the manufacturer's specification on temperature derating.  Take the current at a specific temperature and use the manufacturer's temp rise chart to calculate a 20% deration.  For example, if you are using a 120 amp circuit breaker in an ambient temperature that derates the circuit breaker by 20 amps you can load, you then add an additional 20% deration to meet electrical codes, which means you can power 80 amps of load on a 120 amp circuit breaker.

5) Poles – poles refer to the number of hot lines in a power system.  Circuit breakers come in 1, 2, and 3 poles.  You use 1 pole per phase in your power system.  The amount of poles you use is also dependent on the PDU that is being used in your crypto mine.  If the PDU has a single phase input, then you would use a 1 pole circuit breaker.  If you are using a dual phase input PDU, you would use a 2 pole circuit breaker.  A 3 phase PDU would require a 3 pole circuit breaker.  It is important to know that each pole is rated for the circuit breakers current.  For example, a 3 pole 100 amp circuit breaker is capable of carrying 300 amps of single phase load, or 100 amps per pole.

PDUs

PDUs are the most important part of your power system.  PDUs are the final line of defense against surges, swells, spikes, and noise.  The selection of a PDU drives changes through your whole crypto farm.  For example, if you are using a 3 phase input PDU, you would have to ensure you are using a single phase circuit breaker panel with 1 pole circuit breakers.  One of the largest problems that crypto farms experience when selecting a PDU has to do with a very limited selection of PDUs available on the market that is capable of carrying the amount of current that is required for multiple PSUs.  PSUs usually require between 5 and 10 amps each.  The highest current PDU available on the commercial market that is readily available is usually 30 amps.  This means at most after derating is taken into account, that the PDU can only power 4 to 5 PSUs.  This creates a lot of problems and additional costs.  The first problem is that 30 amp PDUs are typically expensive.  Having multiple 30 amp PDUs will drive costs to ranges that are unacceptable for most crypto mines.  The second problem is that the more PDUs you have, the more wiring and circuit breakers you have to have.  There are many factors to consider when selecting a PDU.

1) Enclosure size – There are 2 types of PDU enclosures commonly used in crypto mines, vertical mount, and horizontal rack mount.  A vertical mount enclosure is typically mounted horizontally to run longways across a shelving rack that houses miners.  By mounting the PDU long ways, it provides a better spread of outlets across the rack and takes up the least amount of space.  A horizontal rack mount enclosure is typically used in an EIA standard 19” rack.  These types of enclosures are popular in server racks in data centers and do not usually work well in a crypto mine environment.  When given a choice, based on your rack set up, always choose a 0U vertical mount PDU.

2) Power configuration – PDUs come in all phase configurations.  It is crucial to choose the PDU that matches your phase configuration.  It is important to note, that usually a 3 phase input PDU will output a single or dual phase, depending on if the 3 phase input is a delta or wye configuration.  A wye configuration will have a single-phase output and a delta configuration will have a dual phase output.  Both single and dual phase power is sufficient to power a PSU. 

3) Protections – PDUs come with an abundance of protection options.  Overload/overcurrent protection is provided by circuit breakers or fuses.  Overvoltage protection is provided by MOVs (metal oxide varistors).  At a minimum, it is important to have circuit protection on each phase of your PDU.  Circuit breakers can be put at the input and/or the output side of your PDU.  Some PDUs have both input and output breakers, but this is not required.  Only output breakers are needed for a crypto mine PDU.

4) Outlet types – PDUs come with many different outlet options.  It is important to use a PDU that has outlets that are rated for your voltage.  A standard 5-15R (wall outlet) is not sufficient to power a miner.  An IEC C-13 or IEC C-19 is the outlet of choice for crypto mine PDUs.  These outlets are rated up to 250V single phase or dual phase.

5) Deration – just like with circuit breaker panels, circuit breakers in PDUs must be derated by 20%.  For example, a 30 amp PDU is sufficient to power up to 26 amps of load. 

In summary, you should always choose the highest current PDU available, while taking into account the space you have available and the way you must mount your PDU onto your rack.

Wiring

Wiring all of the major components of your power system together is a challenge.  You have to take into account the length of the wire run, the voltage, and current that you are using, and the number of conductors.  There are many different types of wire and each type has a place in your power system.

1) THHN – this is the most common type of wiring used. This wire is a single conductor, which means that each wire is carrying a single line.  To complete power wiring you will need a minimum of 3 wires, one for line, one for neutral and one for ground for a single or dual phase system.  In a dual phase system, the wiring would be 2 lines and 1 ground.  THHN is bundled together in a wiring conduit, hollow plastic or metal flexible tubing that is run from point to point.  THHN is the cheapest option when wiring from circuit breaker panels to PDUs.

2) SOOW/SJOW/tray cable – this a multi-conductor cable that houses all of the conductors in the same jacket. These cables usually require a bigger conductor size to carry the same amount of current as a single conductor cable and are typically more expensive these using a THHN single conductor bundle.

3) Gauge – wire comes in various gauges, which is the diameter of the copper conductor of the cable. Use the below chart to pick your wire gauge and always consult with your installation company or an electrician to ensure you are meeting any local electrical codes.

Control and Monitoring

Many control and monitoring software packages exist to manage the power in your crypto mine.  These software packages usually are integrated into the PDUs that are powering your PSUs.  Control and monitoring software can be used to turn individual outlets on and off and to monitor and log current/watt consumption remotely over ethernet.  These powerful features come at a cost and should only be deployed when absolutely needed.  The main advantages to having control and monitoring software are that you can reset miners and monitoring your crypto farm’s power consumption without having to be present at the location and ensure that your loads are balanced across all phases, which helps keep power costs in check.  When deciding on whether or not to use control and monitoring software you need to weigh the costs of having a person on-site vs the initial costs of managing your crypto mine remotely.  Typically, in crypto mines smaller than 5 megawatts, a remotely managed power system is a good value.  If the crypto mine is larger than 5 MW it usually makes sense to deploy remote control and monitoring software.  Additionally, if your mine is a co-location, remote control and monitoring software can be used for billing purposes if you bill based on power usage and to ensure that your client's miners are not over hashing or using more power than you allocated to them.

Compliance

To comply or not to comply, that is the question.  There is a simple answer to this question.  When given a choice, always choose a product that is NRTL listed.  Customized product has a few barriers to being NRTL listed.  Firstly, compliance testing is expensive and labor-intensive.  Secondly, many manufacturers will not NRTL list a short-run customized product due to the labor and paperwork required.  If your crypto mine will be insured or inspected than it will usually require that the power equipment used will have to be NRTL listed.  NRTL listings come in two forms, NRTL listed and NRTL recognized.  NRTL listed products have an official listing and can be used on their own while retaining their listing.  An NRTL recognized product is meant to be part of a larger system that will eventually be NRTL listed.  For example, a circuit breaker in a PDU is NRTL recognized, while the PDU itself would have to be NRTL listed.